Surgical stapling device with dissecting tip

ABSTRACT

A dissecting tip is provided for use with a surgical stapler or instrument. In one embodiment, the dissecting tip is secured to the end effector of the surgical instrument, e.g., to the cartridge assembly. The dissecting tip extends distally from the end effector and is configured to dissect or separate target tissue from certain tissue, e.g., adherent, connective, joined or other tissue.

This application is a continuation application of U.S. application Ser.No. 11/784,115, filed Apr. 5, 2007, which is a continuation of U.S.application Ser. No. 11/030,527, filed Jan. 6, 2005, which is adivisional of U.S. application Ser. No. 10/764,103, filed Jan. 23, 2004,which claims priority from U.S. Provisional Application No. 60/466,378filed Apr. 29, 2003. Each of which are incorporated herein in theirentirety by reference.

BACKGROUND

1. Technical Field

This application relates to a surgical stapling device. Moreparticularly, this application relates to a surgical stapling devicehaving an improved tip construction for accessing and/or separatingtissue.

2. Background of Related Art

Surgical staple or fastener applying devices for joining tissue are wellknown. Typically, such devices include opposing jaw structure forgrasping and clamping selected tissue, wherein one of the jaws of theopposing jaw structure includes a cartridge which houses a plurality ofstaples or fasteners. In some instruments, a knife is provided to cuttissue which has been joined by the staples or fasteners.

Linear surgical stapling devices, for example, include two elongatedmembers which are relatively moveable to capture or clamp tissue.Typically one of the members includes a cartridge which houses aplurality of staples arranged in two or more linear rows and the othermember includes an anvil having a plurality of staple forming pocketsfor receiving and forming the legs of the staples. A knife is movablypositioned between the linear rows of staples such that when thestapling device is positioned about tissue and actuated, the tissue isjoined and/or simultaneously or nearly simultaneously cut.

Linear surgical stapling devices are commonly used during surgicalprocedures to simultaneously seal and cut target tissue, e.g.,vasculature, organs, etc. It is not uncommon during such procedures thatcertain tissue, e.g., vasculature or other adherent, connective, joinedor other tissue, adheres or is joined to the target tissue and mustfirst be separated from the target tissue before the procedure cancontinue. Currently, a surgical device separate from the stapling deviceis used to dissect or separate the certain tissue from the target tissuebefore the target tissue and/or the adherent certain tissue is operatedupon. Also, it is a known practice to attach a guide or carrier tube tothe distal end of the anvil and to use a separate instrument to pass thetube around the target tissue or structure. The tube is also used tomove the back wall of the target tissue into the jaws of the staplingdevice. The tube is removed after the staple is in proper position andthen the stapler is fired. These procedures require extra steps anddevices and can be time consuming and expensive especially duringendoscopic procedures.

Accordingly, a continuing need exists in the art for a device which canbe used not only to join and cut tissue but also to separate or dissectcertain, e.g., adherent, tissue from target tissue.

SUMMARY

In accordance with the present disclosure, a dissecting tip is providedfor use with a surgical stapling device and, especially, a linearsurgical stapling device, including an end effector having an anvilassembly and a cartridge assembly. The dissecting tip is supported onthe end effector, preferably, on the distal end of the anvil assembly.The dissecting tip can instead or also be supported on the distal end ofthe cartridge assembly. The dissecting tip can be positioned to extenddistally from the anvil assembly and includes a body having an outersurface, an inner surface and a distal tip. The body may assume avariety of configurations. For example, the body may include innerand/or outer surfaces which are curved along the longitudinal and/ortransverse axis of the anvil assembly and extend downwardly towards thecartridge assembly. In another preferred embodiment, the inner and/orouter surfaces are substantially flat. In yet another preferredembodiment, the inner and/or outer surfaces include a pair of flatsections interconnected by a curved transition section. Preferably, thewidth of the dissecting tip decreases from the proximal end of thedissecting tip to the distal end of the dissecting tip. The distal tipof the dissecting tip is preferably rounded and blunt to preventsnagging, pulling and/or cutting of tissue.

The dissecting tip functions to dissect or separate target tissue andcertain tissue. As discussed above, “certain tissue” includes adherent,connective, joined or other tissue. This is preferably accomplished bypassing or pressing the outer surface of dissecting tip against thetarget tissue and pushing the distal tip of the dissecting tip behindthe certain tissue such that the certain tissue is positioned adjacentthe inner surface of the dissecting tip. Preferably, the dissecting tipis located and dimensioned to permit access through a trocar cannulaassembly sized to receive the surgical stapling instrument without thedissecting tip.

BRIEF DESCRIPTION OF THE DRAWINGS

Various preferred embodiments of the presently disclosed dissecting tipare described herein with reference to the drawings, wherein:

FIG. 1 is a side top perspective view of a surgical stapling deviceincluding one preferred embodiment of the presently disclosed dissectingtip attached to the end effector thereof;

FIG. 2 is an enlarged view of the indicated area of detail shown in FIG.1;

FIG. 3 is a side view of the end effector with portions broken away andof the dissecting tip of the surgical stapling device shown in FIG. 1with the end effector in the open position adjacent target tissue andcertain tissue which is adhered to the target tissue;

FIG. 4 is a side view of the anvil assembly shown in FIG. 3 with thedissecting tip positioned partially between the certain tissue and thetarget tissue;

FIG. 4 a is a side view of the anvil assembly and dissecting tip shownin FIG. 4 positioned fully between the certain tissue and the targettissue;

FIG. 4 b is a side view of the dissecting tip and end effector shown inFIG. 3 with certain tissue positioned between an open anvil assembly andcartridge assembly;

FIG. 5 is a side view of the dissecting tip and end effector shown inFIG. 4 b with certain tissue positioned between a clamped anvil assemblyand cartridge assembly;

FIG. 5 a is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 1;

FIG. 5 b is a bottom view of the dissecting tip and end effector shownin FIG. 5 a;

FIG. 5 c is a front view of the dissecting tip and end effector shown inFIG. 5 b;

FIG. 5 d is a side perspective view from the front of the presentlydisclosed dissecting tip dissector shown in FIG. 1;

FIG. 5 e is a side view of the dissecting tip shown in FIG. 5 d;

FIG. 6 is an enlarged top side perspective view from the front of theend effector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 6 a is a side view of the dissecting tip and end effector shown inFIG. 6;

FIG. 6 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 6;

FIG. 6 c is a bottom view of the dissecting tip and end effector shownin FIG. 6 b;

FIG. 6 d is a front view of the dissecting tip and end effector shown inFIG. 6 c;

FIG. 6 e is a side top perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 6;

FIG. 6 f is a side view of the dissecting tip shown in FIG. 6 e;

FIG. 7 is an enlarged side top perspective view from the front of theend effector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 7 a is a side view of the dissecting tip and end effector shown inFIG. 7;

FIG. 7 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 7;

FIG. 7 c is a bottom view of the dissecting tip and end effector shownin FIG. 7 b;

FIG. 7 d is a front view of the dissecting tip and end effector shown inFIG. 7 c;

FIG. 7 e is a side top perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 7;

FIG. 7 f is a side view of the dissecting tip shown in FIG. 7 e;

FIG. 8 is an enlarged side perspective view from the front of the endeffector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 8 a is a side view of the dissecting tip and end effector shown inFIG. 8;

FIG. 8 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 8;

FIG. 8 c is a bottom view of the dissecting tip and end effector shownin FIG. 8 b;

FIG. 8 d is a front view of the dissecting tip and end effector shown inFIG. 8 c;

FIG. 8 e is a side perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 8;

FIG. 8 f is a side perspective view from the rear of the dissecting tipshown in FIG. 8 e;

FIG. 8 g is a side view of the dissecting tip shown in FIG. 8 e;

FIG. 9 is an enlarged top side perspective view from the front of theend effector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 9 a is a side view of the dissecting tip and end effector shown inFIG. 9;

FIG. 9 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 9;

FIG. 9 c is a bottom view of the dissecting tip and end effector shownin FIG. 9 b;

FIG. 9 d is a front view of the dissecting tip and end effector shown inFIG. 9 c;

FIG. 9 e is a side perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 9;

FIG. 9 f is a side view of the dissecting tip shown in FIG. 9 e;

FIG. 10 is an enlarged side perspective view from the front of the endeffector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 10 a is a side view of the dissecting tip and end effector shown inFIG. 10;

FIG. 10 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 10;

FIG. 10 c is a bottom view of the dissecting tip and end effector shownin FIG. 10 b;

FIG. 10 d is a front view of the dissecting tip and end effector shownin FIG. 10 c;

FIG. 10 e is a side perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 10;

FIG. 10 f is a side view of the dissecting tip shown in FIG. 10 e;

FIG. 11 is an enlarged side perspective view from the front of the endeffector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 11 a is a side view of the dissecting tip and end effector shown inFIG. 11;

FIG. 11 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 11;

FIG. 11 c is a bottom view of the dissecting tip and end effector shownin FIG. 11 b;

FIG. 11 d is a front view of the dissecting tip and end effector shownin FIG. 11 c;

FIG. 11 e is a side perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 11;

FIG. 11 f is a side view of the dissecting tip shown in FIG. 11 e;

FIG. 12 is an enlarged side top perspective view from the front of theend effector of a surgical stapling device including another preferredembodiment of the presently disclosed dissecting tip;

FIG. 12 a is a side view of the dissecting tip and end effector shown inFIG. 12;

FIG. 12 b is a top view of the dissecting tip and end effector of thesurgical stapling device shown in FIG. 12;

FIG. 12 c is a bottom view of the dissecting tip and end effector shownin FIG. 12 b;

FIG. 12 d is a front view of the dissecting tip and end effector shownin FIG. 12 c;

FIG. 12 e is a side perspective view from the front of the presentlydisclosed dissecting tip shown in FIG. 12;

FIG. 12 f is a side view of the dissecting tip shown in FIG. 12 e; and

FIG. 13 is a schematic diagram of a surgical stapling device includingan embodiment of the presently disclosed dissecting tip extending from acartridge assembly thereof.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred embodiments of the presently disclosed surgical staplingdevice with dissecting tip will now be described in detail withreference to the drawings wherein like reference numerals designateidentical or corresponding elements in each of the several views.

In the description that follows, the term “proximal”, as is traditional,will refer to the end of the stapling device closest the operator andthe term “distal” will refer to the end of the stapling device furthestfrom the operator.

FIG. 1 illustrates a linear surgical stapling device shown generally as10 including an end effector 12 having one preferred embodiment of thepresently disclosed dissecting tip, here generally designated 14,supported thereon. Stapling device 10 also includes a handle assembly 16and an endoscopic portion 18. End effector 12 forms part of a disposableloading unit or single use loading unit (SULU) 20. With the exception ofdissecting tip 14, the remaining components of surgical stapling device10 are substantially as described in U.S. Pat. No. 5,865,361 (“'361patent”), U.S. Pat. Nos. 6,079,606, 6,241,139, 6,330,965 and 6,669,073which are incorporated herein in their entirety by reference. It iscontemplated that the presently disclosed embodiments of the dissectingtip may be used in association with other known linear stapling devicesof both endoscopic and open construction. These devices includearticulating and non-articulating devices as well as reusable andnon-reusable devices. Examples of such devices are disclosed in U.S.Pat. Nos. 6,202,914, 6,250,532, 6,109,500, 6,032,849, 5,584,425,5,540,375, 5,554,169, 5,507,426, 5,482,197, which are also incorporatedherein in their entirety by reference. In light of the comments above,only the preferred embodiments of the dissecting tips disclosed hereinwill be discussed in detail in this application.

FIGS. 1-5 c illustrate one preferred embodiment of the presentlydisclosed dissecting tip in combination with a surgical stapling device10. As discussed above, surgical stapling device 10 includes a handleassembly 16, an elongated body or endoscopic portion 18, and a SULU 20.Briefly, handle assembly 16 includes a stationary grip member 22, apivotable trigger 24, an articulation lever 26, a rotation knob 27 andreturn knobs 28. SULU 20 is adapted to be releasably attached toelongated body portion 18 and includes a proximal body portion 32 andend effector 12. End effector 12 is pivotally attached to proximal bodyportion 32 to facilitate articulation of end effector 12 in relation toproximal body portion 32.

End effector 12 includes an anvil assembly 34 and a cartridge assembly36 which houses a plurality of linear rows of staples. Anvil assembly 34and cartridge assembly 36 are movable, here, pivotal in relation to eachother between an open position and a clamped or approximated position.Pivotable trigger 24 is actuable through an actuation stroke or strokesto move anvil assembly 34 in relation to cartridge assembly 36 betweenthe open position and the clamped position and to eject staples fromcartridge assembly 36. The operation of each of these components isdescribed in greater detail in the '361 patent and will not be discussedin further detail herein.

Dissecting tip 14 is secured to a distal end of the end effector 12.Alternately, dissecting tip may be integrally formed with end effector12 or end effector 12 and dissecting tip 14 may be of monolithicconstruction. In one preferred embodiment, dissecting tip 14 is securedto a distal surface of anvil assembly 34 which is contiguous with atissue contact surface 34 a of anvil assembly 34. Dissecting tip 14 ispreferably formed from a surgical grade metal or plastic and is attachedto anvil assembly 34 using any known suitable fastening technique, e.g.,adhesives, welding, soldering, brazing, pins, etc. Alternately, otherknown surgically approved materials may be used to construct dissectingtip 14. In this preferred embodiment, dissecting tip 14 includes acurved preferably smooth inner surface 14 a, preferably also a curved,smooth outer surface 14 b and a rounded preferably thin blunt tip 14 c.The curved surface can be formed by any suitable radius. A one inchradius has been found suitable for certain applications. Curved innersurfaces may be formed by a plurality of curves, wherein each of thecurves is defined by a radius of curvature. Smooth surfaces preventdissecting tip 14 from snagging, pulling and/or cutting tissue. Innersurface 14 a of dissecting tip 14 extends downwardly towards cartridgeassembly 36 to a location beyond the distal end of cartridge assembly36. By extending dissecting tip 14 beyond cartridge assembly 36, accessto adherent tissue is improved and visualization of the tip to confirmproper position and that dissection of the adherent tissue is completedis permitted. The width of the dissecting tip 14 decreases from itsproximal end to its distal end and at its greatest with is smaller thanthe width of cartridge assembly 36. Desirably there are substantiallysmooth blends or transitions from the dissecting tip to the portion(s)of the jaw structure to which the tip is secured or from which itextends. When anvil assembly 34 and cartridge assembly 36 are in theclamped or approximated position, dissecting tip 14 is spaced from adistal angled tissue guide surface 36 a of cartridge assembly 36.Preferably, the space therebetween is at least the same, or preferablygreater, e.g., two times greater, than the gap between the tissuecontacting surfaces of the anvil and cartridge assemblies when they areapproximated. However, there may be instances when it may be desired tohave less space between the dissecting tip and the tissue guide surfaceof the cartridge, for example when it is desired to compress tissuethere.

Referring now to FIGS. 3-5, when surgical stapling device 10 is used todissect certain tissue 40, e.g., blood or airway vessels, from targettissue 42, e.g., stomach, lung, etc., curved outer surface 14 b ofdissecting tip 14 can be pressed or passed against the target tissue 42and slid behind certain tissue 40, e.g. adherent tissue, to separateand/or dissect tissue 40 from, for example, adherence with target tissue42. Positioning of dissecting tip 14 behind certain tissue 40 ispreferably accomplished with the anvil assembly 34 and the cartridgeassembly 36 in the open position. Alternatively, the anvil and cartridgeassemblies can be moved to the clamped position to provide extrastability to the end effector during dissection of tissue. Thereafter,either or both of certain tissue 40 and target tissue 42 can beindependently joined and cut by clamping and actuating surgical staplingdevice 10.

It is noted that although not described in detail, end effector 12preferably is adapted to access the surgical site through a trocarcannula assembly as is known in the art. To accomplish this, anvilassembly 34 and cartridge assembly 36 are maintained in a clampedposition as elongated body portion 18 and end effector 12 are insertedthrough the cannula (not shown). As illustrated, preferably, dissectingtip 14 does not extend below a plane defined by a bottom surface 36 b ofcartridge assembly 36, nor does dissecting tip 14 extend outwardlybeyond the sidewalls of cartridge assembly 36. The dissecting tip can bepositioned above, preferably slightly above, the plane. As such,surgical stapling device 10 including dissecting tip 14 may be used witha trocar cannula assembly sized to receive a surgical stapling devicenot having a dissecting tip 14.

FIGS. 6-6 e illustrate another preferred embodiment of the presentlydisclosed dissecting tip shown generally as 114. Dissecting tip 114 issecured to the distal end of end effector 12. Alternately, dissectingtip 114 can be monolithically or integrally formed with end effector 12.As discussed above, end effector 12 includes anvil assembly 34 andcartridge assembly 36. Dissecting tip 114 is secured to a distal surfaceor portion of anvil assembly 34 in the manner described above withrespect to dissecting tip 14. Dissecting tip 114 is also constructedfrom a surgical grade metal or plastic and includes substantially flatinner and outer surfaces 114 a and 114 b and a rounded, blunt tip 114 c.The use of other known surgically approved materials to constructdissecting tip 114 is envisioned. Other tip configurations may also beemployed. The outer edges 114 d of outer surface 114 b are preferablyrounded to prevent snagging, and/or cutting of tissue. Inner surface 114a of dissecting tip 114 is preferably substantially parallel to andspaced from tissue guide surface 36 a of cartridge assembly 36 whenanvil assembly 34 and cartridge assembly 36 are in the clamped position.Distal tip 114 c of dissecting tip 114 extends distally beyond thedistal end of cartridge assembly 36 and decreases in width from itsproximal end to its distal end. The width of the proximal end ofdissecting tip 114 is smaller than the width of cartridge assembly 36and distal tip 114 c preferably does not extend below a plane defined bya bottom surface 36 b of cartridge assembly 36. As such, a surgicalstapling device including dissecting tip 114 can be inserted through atrocar cannula assembly sized to receive the stapling device.

The use of dissecting tip 114 is substantially identical to that ofdissecting tip 14 and will not be discussed in further detail herein.

FIGS. 7-7 e illustrate another preferred embodiment of the presentlydisclosed dissecting tip shown generally as 214. Dissecting tip 214 issecured onto anvil assembly 34 of end effector 12 in the mannerdescribed above with respect to dissecting tip 14. Dissecting tip 214 isalso constructed from a surgical grade metal or plastic. Alternatively,the use of other known materials of construction is envisioned.

Dissecting tip 214 includes inner and outer surfaces 214 a and 214 b anda blunt tip 214 c. Inner and outer surfaces 214 a and 214 b preferablyeach have a substantially flat proximal portion 250 a and 250 b and asubstantially flat distal portion 252 a and 252 b positioned at an angleto proximal portion 250. Preferably, proximal portion 250 and distalportion 252 along inner surface 214 a define an angle θ (FIG. 7 a) ofbetween about 10° and about 90°, and most preferably about 30°. Thetransition between proximal portion 250 a and distal portion 252 a issmooth and rounded to prevent snagging, pulling and/or cutting oftissue. The outer surface of tip 214 can have other shapes, e.g.,rounded as in FIGS. 1-5 e. As discussed above with respect to dissectingtips 14 and 114, the width of dissecting tip 214 decreases from itsproximal end to its distal end and at its greatest width is less thanthe width of cartridge assembly 36. The distal end of distal portion 252a includes a blunt tip 214 c which preferably does not extend beyond aplane defined by a bottom surface 36 b of cartridge assembly 36. The useof dissecting tip 214 is substantially identical to that of dissectingtip 14 and will not be discussed in further detail herein.

FIGS. 8-8 e illustrate another preferred embodiment of the presentlydisclosed dissecting tip shown generally as 314. Dissecting tip 314includes an inner surface 314 a, a top surface 314 b and a front surface314 c. Inner surface 314 a is angled and is substantially parallel todistal angled tissue guide surface 36 a of cartridge assembly 36. Topsurface 314 b is curved or concave along an axis transverse to alongitudinal axis of anvil assembly 34. Front surface 314 c is angleddownwardly towards cartridge assembly 36 and preferably defines an angleθ (FIG. 8 a) of between about 95° and 135° with respect to thelongitudinal axis of anvil assembly 34. More preferably, angle θ isabout 106°. The width of dissecting tip 314 decreases from a proximalend of dissecting tip 314 to the distal end of dissecting tip 314. Thewidth at the proximal end of dissecting tip 314 is approximately equalto the width of cartridge assembly 36. As discussed above, thedimensions and positioning of dissecting tip 314 on stapling device 10permit positioning of stapling device 10 through a trocar cannulaassembly sized to allow passage stapling device 10.

Distal tip 314 d of dissecting tip 314 is preferably positionedproximally of the distal end of cartridge assembly 36. Alternately,distal tip 314 d may be positioned adjacent to or distally of the distalend of cartridge assembly 36.

Dissecting tip 314 includes a substantially hollow recess 314 e (FIG. 8f) which is configured to receive the distal end of anvil assembly 34.Dissecting tip 314 may be positioned over the distal end of anvilassembly 34 and secured thereto using any known fastening technique,e.g., adhesives, welding, friction fit, pins, screws, etc. Dissectingtip 314 is preferably formed from surgical grade metals or plasticsalthough other known materials of construction are envisioned.Dissecting tip 314 functions basically in the same manner as discussedabove with respect to dissecting tip 14 and will not be discussed infurther detail herein.

FIGS. 9-9 e illustrate another preferred embodiment of the presentlydisclosed dissecting tip shown generally as 414. Dissecting tip 414 issimilar in shape to dissecting tip 314 but includes a peg extension 436(FIG. 9 e) to secure dissecting tip 414 to anvil assembly 34, ratherthan a hollow recess as will be further discussed below. Dissecting tip414 includes an inner surface 414 a, a top surface 414 b, and a frontsurface 414 c. Inner surface 414 a preferably is substantially parallelto a tissue guide surface 36 b on the distal end of cartridge assembly36. Top surface 414 b is flat and is positioned to abut against a distalsurface of anvil assembly 34 which is contiguous with an inner tissueengaging surface 34 a of anvil assembly 34. Front surface 414 c isangled downwardly towards cartridge assembly 36 and preferably definesan angle θ (FIG. 9 a) of between about 95° and about 135°. Morepreferably, angle θ is about 154°.

Peg extension 436 is a T-shaped member which extends upwardly from aproximal end of top surface 414 b of dissecting tip 414. The upperportion 452 of T-shaped member 436 extends transversely across anvilassembly 34 and is dimensioned to be received in a linear slot (notshown) formed in the distal end of anvil assembly 34. To attachdissecting tip 414 to anvil assembly 34, upper portion 452 of T-shapedmember 436 is positioned within the distal linear slots of anvilassembly 34 and dissecting tip 414 is rotated 90° to lock upper portion452 within the linear slot and lock dissecting tip to anvil assembly 34.Additional fastening techniques may be used to fixedly secure dissectingtip 414 to anvil assembly 34, e.g., adhesives, welding, etc.

FIGS. 10-10 e illustrate another preferred embodiment of the presentlydisclosed dissecting tip shown generally as 514. Dissecting tip 514 issubstantially similar to dissecting tip 314 in construction but differsin that a distal tip 514 d of dissecting tip 514 is narrower than andpositioned above, over or adjacent to the distal end of cartridgeassembly 36. Further, front surface 514 c which preferably defines anangle θ (FIG. 10 a) of between about 95° and about 135° is preferablyabout 115°. As discussed above with respect to dissecting tip 314,dissecting tip 514 defines a hollow recess (not shown) dimensioned andconfigured to receive the distal end of anvil assembly 34.

FIGS. 11-1 e illustrate yet another preferred embodiment of thepresently disclosed dissecting tip shown generally as 614. Dissectingtip 614 is substantially similar to dissecting tip 514 with theexception that dissecting tip 614 includes a pair of cutouts 614 cformed in opposite tapered sidewalls 614 a and 614 b thereof. Thetapered sidewalls 614 a and 614 b and cutouts 614 c provide a smoothtransition from dissecting tip 614 to anvil assembly 34 to preventsnagging and pulling of tissue.

FIG. 12-12 e illustrate another preferred embodiment of the presentlydisclosed dissecting tip shown generally as 714. Dissecting tip 714 isformed integrally and/or monolithically with an anvil plate 34 a (FIG.12 e) of anvil assembly 34 and is therefore preferably formed from asurgical grade metal. Dissecting tip 714 includes an inner surface 714a, an outer surface 714 b and a distal tip 714 c which preferably isrounded. Inner and outer surfaces 714 a and 714 b are substantially flatand define an angle θ of preferably between about 105° and about 155° inrelation to a longitudinal axis of anvil assembly 34. More preferably θin about 136° Dissecting tip 714 extends downwardly towards cartridgeassembly 36, at angle θ which is preferably less than an angle B definedbetween tissue guide surface 36 a formed on the distal end of cartridgeassembly 36 and a longitudinal axis of cartridge assembly 36. Althoughthe invention of this disclosure can be employed on any sized SULU orend effector, for some applications shorter end effectors may bepreferred.

It is preferred that the junction, blend or transition of the proximalportion of the inner surface of dissecting tip 14 with the plane oftissue contacting surface 34 of the anvil assembly be axially distal ofthe junction, blend or transition of tissue guide surface 36 a and thetissue contacting surface of cartridge assembly 36. This provides spaceto allow tissue to be squeezed distally of the staple working portionsof the tissue contacting surfaces of anvil assembly 34 and cartridgeassembly 36 and helps maintain the desired tissue gap between thosesurfaces, during approximation and clamping. The configuration ofdissecting tip 714 of end effector 12 shown in FIG. 12 a exemplifiesthis preferred junctional relationship.

It will be understood that various modifications may be made to theembodiments disclosed herein. For example, the dissecting tip may besecured to other parts of the end effector including the cartridgeassembly (FIG. 13). Further, each of the dissecting tips may bemonolithically or integrally formed with the end effector, e.g., anvilassembly or cartridge assembly. Moreover, the angles and/or curves ofthe dissecting tip surface(s) may be modified to better suit aparticular surgical procedure. Therefore, the above description shouldnot be construed as limiting, but merely as exemplifications ofpreferred embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appended hereto.

What is claimed is:
 1. A surgical stapling device comprising: anelongated body portion; an end effector including an anvil assemblymovably supported in relation to a cartridge assembly between an openposition and a clamped position, the cartridge assembly having aplurality of staples supported therein; a dissecting tip extendingdistally from a distal end of the cartridge assembly and towards theanvil assembly in the distal direction, the dissecting tip having ablunt distal end configured to separate target tissue from certaintissue.
 2. A surgical stapling device according to claim 1, wherein thedissecting tip includes smoothly curved inner and outer surfaces.
 3. Asurgical stapling device according to claim 2, wherein the distal end ofthe dissecting tip extends distally beyond the distal end of the anvilassembly.
 4. A surgical stapling device according to claim 3, whereinthe curved inner surface is formed by plural curved radii.
 5. A surgicalstapling device according to claim 4, wherein the width of thedissecting tip decreases from the proximal end of the dissecting tip tothe distal end of the dissecting tip.
 6. A surgical stapling deviceaccording to claim 5, wherein the dissecting tip is monolithicallyformed with the cartridge assembly.
 7. A surgical stapling deviceaccording to claim 5, wherein the dissecting tip is secured to thecartridge assembly using a mechanical fastening technique.
 8. A surgicalstapling device according to claim 1, wherein the curved inner surfaceof the dissecting tip is contiguous with an inner tissue contact surfaceof the cartridge assembly.
 9. A surgical stapling device according toclaim 1, wherein the dissecting tip does not extend below a planedefined by an outer surface of the anvil assembly.
 10. A surgicalstapling device according to claim 1, wherein the anvil assemblyincludes a tissue contacting surface and an outer surface opposite thetissue contacting surface, the dissecting tip terminating between aplane defined by the tissue contacting surface of the anvil assembly anda plane defined by the outer surface of the anvil assembly when the endeffector is in the clamped position.
 11. A surgical stapling deviceaccording to claim 1, wherein the elongated body portion, the endeffector and the dissecting tip are configured to be received through anaccess port.
 12. A surgical stapling device comprising: an elongatedbody portion; an end effector including an anvil assembly movablysupported in relation to a cartridge assembly between an open positionand a clamped position, the anvil assembly including a tissue contactingsurface and an outer surface opposite the tissue contacting surface; adissecting tip extending distally from a distal end of the cartridgeassembly and towards the anvil assembly in the distal direction, whereinthe dissecting tip terminates between a plane defined by the tissuecontacting surface of the anvil assembly and a plane defined by theouter surface of the anvil assembly when the end effector is in theclamped position.